Facial Animations not showing up in Unity
Facial animation with combined blendshapes (=shape keys) and bones in a game engine is quite involved. You have to do quite a bit of programming combine those two things.

You can create Blendeshapes and make the animations based purely on those shapekeys directly in Unity. But you can't use bones to drive Blendshapes like you can in Blender. See https://docs.unity3d.com/Manual/BlendShapes.html

Or you can use a bones-only approach for facial animation, that would be the simplest method from a technical perspective, but it can be quite hard to do a good facial rig with only bones.